In communication networks, network energy efficiency is a key performance indicator (hereinafter referred to as KPI) to measure a useful output of network unit energy consumption. Currently, for a measurement method and an assessment mode of the network energy efficiency, the energy efficiency (hereinafter referred to as EE) project of European telecommunications standards institute (hereinafter referred to as ETSI) has performed modeling and analysis to base station equipments in a radio access network (hereinafter referred to as RAN), and a method for measuring the energy consumption on the network equipment level and site-level, as well as an energy efficiency assessment mode on the network level are proposed. The ETSI also defines that the network energy efficiency is a relationship between the energy consumption and the useful output of the energy consumption. With the growth in the number of users and the rapid growth in data services, operators are increasingly attaching importance to a status of the network energy efficiency.
Two kinds of cell-level energy saving use cases are proposed in the 3GPP, one for a cell overlaid and the other one for capacity limited network (they are collectively referred to as a network with overlaid coverage), and there is no specific method in the prior art to assess the energy efficiency KPI for these cell-level energy saving use cases, so the operators can not know the actual gain of the energy efficiency brought by the cell energy saving.